Application Strategies Of Valence-Category Two-Dimensional Diagram In Review Teaching Of Elements And Their Compounds

In 2017,the Ministry of Education introduced a new chemistry curriculum in high schools,requiring the curriculum design to cultivate students’ multiple skills,whose study of elements and compounds can greatly improve students’ practical ability,thinking ability,scientific inquiry ability,environmental awareness,social responsibility and comprehensive ability.However,the scattered knowledge of elements and their components makes it difficult to remember and easy to forget,leading to the weak link in the process of chemistry review.To further improve students’ comprehensive literacy,there is an urgent need to find suitable tools for learning situations and efficient review of elements and their compounds.First appeared in the compulsory chemistry textbook of Shandong edition,the valence class two-dimensional graph takes the substance type as the abscissa and the element valence as the ordinate.The reducing or oxidizing properties of a substance are determined by the valence of the core elements and the properties of the substance divided by substance classes.By distributing them in a coordinate map with different valence,the knowledge of the same element is more systematic and logical.From the perspective of chemical valence change,it further strengthens the understanding of REDOX reactions.As an effective teaching method,valence class two-dimensional graph has been paid more and more attention and studied in recent years.At present,the research on valence class two-dimensional graph lacks certain pertinence and high efficiency of practical operation.First of all,there is a certain gap between them and senior three students in similar schools,so they are not completely suitable for use.Secondly,the structural application mode of knowledge on elements and their compounds is not clear in the specific operation level of teaching practice.Based on the current situation of senior three students in Yuqing High School,it proposes the "Five-period" model construction method using the valency class two-dimensional graph application tool for the review teaching of elements and their compounds.It explores the "2+2" teaching method for the second round of review teaching of elements and their compounds,then designs "Iron and its Important Compounds","Sodium and its Important Compounds" and practical typical teaching cases.Therefore,it chooses valence class two-dimensional graph as a tool for the review teaching of elements and their compounds in senior three.According to the actual learning situation,it explores the effective application strategies suitable for similar schools to review elements and their compounds by valence class two-dimensional graph.Through staged teaching practice,the results of horizontal and vertical comparison of test scores,combined with students’ review of elements and their compounds using valence-like two-dimensional diagrams,and teachers’ real feedback teaching after using valence-like two-dimensional diagrams,show that the proposed method based on valence-like two-dimensional diagrams in this paper-The "five-hour" model construction method and the "2+2" method of quasi-bimap can effectively help senior three students to review the knowledge of elements and their compounds,and improve the efficiency of classroom teaching.It has laid a foundation for high school teachers to create an efficient classroom,and has certain directivity for follow-up related research.